1. Field of Invention
This invention relates to a low cost rapid response diagnostic system to determine cortisol levels in patients selected as potential candidates for GCR (glucocorticoid receptor) antagonist therapy utilizing a GCR antagonist, such as ORG 34517. The rapid, sensitive, and inexpensive test can be used to determine patients who have non-normal cortisol production or disordered circadian rhythms as a method for selecting subjects for GCR antagonist therapy for whom it is likely to have beneficial and/or therapeutic effects, and can also be used to monitor changes in cortisol levels in response to treatment.
2. Description of Related Art
ORG 34517 is one of a class of therapeutic agents designed to block the glucorticoid receptor (GR), acting as an antagonist for endogenous cortisol. Its primary developmental pathway has been as a treatment for neuropsychiatric diseases that are characterized by dysregulated signaling in the hypothalamic-pituitary-adrenal axis, often with higher than normal circulating levels of endogenous cortisol. Of particular note are the phase 2 clinical trials that have been completed for the treatment of psychotic depression. Other possible uses in this disease category which are under investigation include: post-traumatic stress disorder, weight gain in patients requiring long term anti-psychotic medication, hospital delirium of the elderly, etc. In addition, the diverse data indicate a possible role for GR-blockade as a means of promoting chemo-sensitization of target tumors. Pre-clinical trials demonstrate significant outcomes—breast cancer growth slowed and reversed. These are pre-clinical trials in which the company has successfully demonstrated the efficacy of a chemotherapy sensitizer for “triple negative” breast cancer.
The “triple negative” breast cancer is the most difficult to treat type of breast cancer, and is indicated by the patient testing negative for estrogen-receptor, progesterone-receptor and her-2/neu. The triple negative breast cancer is resistant to chemotherapy. Primary drug resistance and early onset of resistance are seen in other tumor types, as well, for example in liver and ovarian cancers, where there is a significant unmet medical need for effective therapy. Chemotherapy is still a key approach to cancer treatment. Chemosensitizers would contribute to improve the efficacy of current therapeutic drugs and potentially improve their side effect profile. The world cancer market was estimated at $23 billion in 2004 and is expected to grow to at least $61 billion by 2013 with a CAGR of 14.7%. U.S. Patent Application Publication no. 2011/0269728 (Pan et al.), incorporated by reference herein in its entirety, discloses a method of killing breast cancer cells comprising administering to a breast cancer patient an effective amount of a combination of anti-cancer compounds, wherein the anticancer compounds comprise a glucocorticoid receptor antagonist and a chemotherapeutic.
The present invention provides a low cost rapid response diagnostic system to determine salivary cortisol levels in patients selected as potential candidates for GCR (glucocorticoid receptor) antagonist therapy utilizing a GCR antagonist such as ORG 34517. The inventors have developed a saliva based diagnostic device for cortisol detection to accompany the development of ORG34517 as a therapeutic agent for multiple indications.
Clinical testing of cortisol levels in patients is a high cost, laborious test that can be salivary or serum, with samples taken from a patient and sent to a lab to await results. The cost and time factor for such tests has, to date, been prohibitive, preventing the rapid quantitative determination necessary to assign treatment with a glucocorticoid receptor (GCR) antagonist due to the inability to make the determinations of cortisol levels at point of need or to monitor changes in cortisol as a measure of treatment response. By allowing the physician to determine the elevated cortisol level of a patient and in turn provide a therapeutic for such elevation at point of measurement, the physician can qualify the best candidates suited for this type of therapeutic. The system also enables continual monitoring of the patient during treatment for assessment of responsiveness to treatment.
The present invention provides a system in which an apparatus uses a high void volume carrier to absorb sufficient amounts of saliva to then be placed into a reaction vessel with a reagent. The reagent is mixed with the sample and then is combined with, for example, a fluorescent ligand or pigment-labeled ligand and placed into a device to determine salivary cortisol levels of the patient in less than 5 minutes, in either a portable, miniaturized fluorescence polarization reader (in the former case) or into a lateral flow device (in the latter) for measuring amounts of substrate in a small amount of fluid by direct or indirect methods.
The reader apparatus, for example, provides temperature control and on-board mixing as an aid in viscosity control of the reaction to ensure better accuracy and precision.
The invention and method for non-invasive sampling and detecting the presence of a biological substance of interest in a test sample of, for example, saliva, or a bodily fluid, combining said test sample with a buffering system (Reagent 1) containing viscosity controllers and stabilizers in a reaction vessel, mix solution well, combining said test sample and buffering system mixture with a fluorescence-labeled ligand (Reagent 2) to said biological substance (assay solution) in a reaction vessel, mix solution well, and detecting a change of the assay solution in the fluorescence polarization reader, or a pigment labeled ligand.
The present invention relates to the use of glucocorticoid receptor (GCR) antagonists (e.g. ORG 34517) enabled by a device for rapidly, sensitively, specifically quantifying salivary cortisol levels as a surrogate for serum cortisol levels in a low cost manner. One purpose of this combination of inventions is to determine patients who have non-normal cortisol produced by the adrenal cortex or disordered circadian rhythms as a method for selecting subjects for GCR antagonist therapy for whom it is likely to have beneficial and/or therapeutic effects, i.e., those with abnormal high levels (but maintained circadian rhythm), over responsiveness to normal levels, high night-time cortisol levels as a feature of disrupted circadian rhythm. The rapid, sensitive, and inexpensive test can also be used to monitor changes in cortisol levels in response to treatment, in patients who have non-normal cortisol produced by the adrenal cortex or disordered circadian rhythms as a method for selecting subjects for GCR antagonist therapy for whom it is likely to have beneficial and/or therapeutic effects, but also in patients having normal baseline cortisol at the start of treatment, but for whom changing cortisol levels during treatment will indicate responsiveness to the GCR antagonist.
The endogenous glucocorticoids are steroids predominantly produced in the adrenal cortex. Glucocorticoids are important steroids for intermediary metabolism, immune, musculosceletal, connective tissue and brain function. The main glucocorticoid in the body is cortisol. The production and secretion of cortisol is governed by a complex and highly efficient system that includes the hypothalamus, pituitary and the adrenal glands i.e., hypothalamic-pituitary-adrenal axis (HPA). Cortisol secretion has a circadian release rhythm with peak values in early morning and trough values at midnight.
The production and secretion of the most important glucocorticoid, cortisol, is governed by a complex and highly efficient system that includes the hypothalamus, pituitary and the adrenal glands i.e., hypothalamic-pituitary-adrenal axis. Cortisol secretion is regulated by the suprachiasmatic nucleus of the hypothalamus into a circadian release rhythm. The timing is synchronized with the solar day by dark-light shifts, which normally reflect the habitual sleep-wake pattern. Therefore in healthy persons, the cortisol secretion has a 24-hour circadian pattern with peak serum levels in the early morning, 3-6 hours after onset of sleep, and nadir levels around midnight. Physical and psychological stressors also activate cortisol secretion. Changed patterns of serum cortisol levels have been observed in connection with abnormal adrenocorticotropic hormone (ACTH), levels, clinical depression, psychological stress, and physiological stressors such as hypoglycemia, illness, fever, trauma, surgery, fear, pain, physical exertion, or temperature extremes. Cortisol levels and responsiveness may also differ from normal for elderly individuals and in individuals with autism or Asperger's syndrome.
Glucocorticoids (GCs) such as, in humans, cortisol, perform several important functions. These include participating in the regulation of carbohydrate, protein and fat metabolism by signaling the liver to make glucose and glycogen, the adipose tissues to release lipids and fatty acids into the bloodstream, and the skeletal muscles to release proteins or amino acids into the bloodstream. GCs also decrease bone formation.
GCs also regulate the body's inflammatory response as well. GCs are part of the feedback mechanism in the immune system that inhibits immune activity (i.e., inflammation). GCs cause their effects by binding to the GCR. The activated GCR complex in turn up-regulates the expression of anti-inflammatory proteins in the nucleus (a process known as transactivation) and represses the expression of pro-inflammatory proteins in the cytosol by preventing the translocation of other transcription factors from the cytosol into the nucleus (transrepression) (Rhen T and Cidlowski J A. NEJM 2005; 353: 1711-23).
GCR antagonist therapy is helpful in patients with abnormally high levels of cortisol (but maintained circadian rhythm), over responsiveness to normal levels, or high night time cortisol levels as a feature of disrupted circadian rhythm. Successful therapeutic use of such agents is thus dependent on determining circadian cortisol levels (either peak levels during the day, e.g., at noon, or measurements taken every 4 hours or 6 hours over a 24 hour period). This combined system of salivary cortisol quantification as an enabling device for its paired GCR antagonist will identify individuals for whom GCR antagonist therapy has a benefit.
The glucocorticoid receptor (GR) is expressed at high levels in some normal tissues, but not in others. Likewise, malignant tumors of diverse types and sites have variable GR expression. When present in normal or tumor (benign or malignant) tissues, this GR expression may be variously located in some or all of their cellular sub-compartments: 1. stem cells; 2. progenitor (so called “transit amplifying”) cell descendents of activated stem cells; and 3. differentiated progeny of activated stem or progenitor cells.
As an example, in the gastrointestinal tract, GR are highly expressed in esophageal squamous epithelia, hepatocytes, and pancreatic islet cells, but are not highly expressed in other gastrointestinal epithelia (stomach, small and large intestines, pancreatic and biliary ducts). In corresponding malignancies arising in these epithelia, hepatocellular carcinoma (HCC) and squamous cell carcinomas (SCC) of the esophagus have consistently high GR expression. Gastric and colorectal adenocarcinomas have little to no GR expression.
Dexamethasone (DEX), a binding activator of GR, has been found to confer chemoresistance in oesophageal SCC and HCC cells, suggesting that GR expression may be biologically important in some GR-expressing carcinomas. This not only suggests why DEX or other glucocorticoids are not useful in treatment of these malignancies, but it implies that endogenous, circulating cortisol itself may actually promote chemoresistance, even in the absence of iatrogenic glucocorticoid administration. Therefore, these findings suggest that blockade of GR within such malignant tumors, by preventing activation by endogenous, circulating cortisol, can play a role in maintaining or promoting chemosensitivity and/or treating neoplasia.
The present invention therefore relates to the use of GR antagonists (e.g., ORG 34517, RU486, and others) for the treatment of, for example, esophageal SCC and HCC or other tumors with high GR expression as a means of inhibiting promotion of chemoresistance by endogenous cortisol. These effects may be present in all tumor cells or, when tumors have stem or progenitor cell compartments, these, specifically, as well. Thus, the present invention relates to the inhibition of chemoprevention in the bulk of cells making up a given tumor and/or in the rare stem/progenitor cells within the tumor that are often responsible for tumor resistance to therapy and re-occurrence, i.e., as a novel, targeted “cancer stem cell” treatment.
To avoid possible negative side effects of systemic blockade of GR, the present invention further relates to localized tumor treatment with GR antagonists through direct vascular infusion of tumor feeding vessels or by direct, intratumoral injection.
The present invention relates to the use of GR antagonists for the treatment of, for example, breast and other cancers. The invention is based on the observation that GR inhibition will increase tumor cell susceptibility. GR antagonists will block anti-apoptotic GR signaling in GR-overexpressing breast cancer cells and subsequently render breast cancer cells more susceptible to conventional and novel cytotoxic therapies (via blocking GR's pro-cell survival signaling pathway).
All references cited herein are incorporated herein by reference in their entireties.